摘要:
An oxidation catalyst is provided which is capable of combusting PM in a diesel engine exhaust gas at a low temperature and which has low degradation due to heat generated during combustion (i.e., has high heat resistance). A composite oxide for an exhaust gas purification catalyst is formed from Ce, Bi, R, R', and oxygen, and when the molar ratios of Ce, Bi, R, and R' are expressed as Ce:Bi:R:R' = (1 -x-y - z) :x:y:z, it satisfies 0
摘要:
A catalyst supporting body 1 has a porous honeycomb base body 2 having a porosity within a range of 40 to 60 vol.%. The body 2 has a plurality of cells 22 partitioned by cell walls 21 arranged in a lattice-like shape. A coated catalyst layer 3 made of a porous body having a void fraction of void spaces within a range of 50 to 63 vol.% is particularly supported on surfaces of the cell walls 21 and in pores 216 formed in the cell walls 21 by a filling rate of not less than 40 vol.%. In an immersing step of a manufacturing method, a combination of a kind of catalyst slurry and the porous honeycomb base body is selected so that a cumulative-frequency at an intersection point between a pore distribution map and a particle size distribution map becomes not less than 80 %. The pore distribution map indicates a relationship between pore sizes of pores in the porous honeycomb base body and a cumulative-frequency of the pores. The particle size distribution map indicates a relationship between particle size in the catalyst slurry and a cumulative-frequency of the particles.
摘要:
Pour fabriquer un kilogramme d'un catalyseur de dénitrification, on prépare une suspension en mettant en contact, dans 4 à 20 litres d'eau, à la fois entre 600 et 800 grammes d'oxyde de titane divisés, présentant une forme anatase et ayant une surface spécifique comprise entre 70 et 400 m 2 /g, et un sel de manganèse (II) soluble et un sel de fer (III) soluble, dans des proportions telles que le rapport molaire manganèse/fer est compris entre 2 et 4, et dans des quantités telles que la quantité totale de fer et de manganèse est comprise entre 20 et 35 % en poids du catalyseur fabriqué ; puis, tout en maintenant la suspension sous agitation pendant au moins 10 minutes on y ajoute une solution d'un agent précipitant et alcalin de façon à remonter le pH de la suspension à une valeur comprise entre 8 et 9,5 ; puis on soumet la suspension à une évaporation d'eau à une température comprise entre 80°C et 130°C ; puis on obtient le catalyseur en procédant à une calcination du produit résultant de l'évaporation d'eau, cette calcination étant réalisée pendant au moins une heure à une température comprise entre 400 °C et 600°C.
摘要:
An object of the present invention is to provide an oxidation catalyst (DOC) which, even after long-term use thereof, is suitable for combustion, at a relatively low temperature, of a light oil component supplied upon regeneration of a diesel particulate filter (DPF), and which exhibits excellent thermal resistance and excellent durability. The oxidation catalyst (DOC) of the present invention suitable for combustion of a light oil component contains an alumina porous body whose pore size distribution profile, as determined by means of a mercury porosimeter, has a peak falling within a range of 10 to 100 nm, and a noble metal supported on the surface of the alumina porous body and/or on the inner walls of pores of the alumina porous body. The oxidation catalyst (DOC) product of the present invention includes a catalyst support made of a ceramic or metallic material, and the aforementioned oxidation catalyst (DOC) supported on the catalyst support.
摘要:
The present invention details a process for producing a catalyst powder. The steps of the process include preparing catalyst slurry, drying, pyrolyzing, and calcining the catalyst slurry to obtain a calcined catalyst powder. The catalyst slurry comprises a catalyst, a liquid carrier, a templating agent, and a catalyst substrate. The catalyst slurry is dried to obtain a raw catalyst powder. The raw catalyst powder is heated in a first controlled atmosphere to obtain a pyrolyzed catalyst powder and the pyrolyzed catalyst powder is calcined in a second controlled atmosphere to obtain a calcined catalyst powder. A method of fabricating a catalyst surface and catalytic converter using the prepared catalyst powder is also illustrated.
摘要:
Methods and apparatuses are provided for protecting a catalyst (56) within a combustor (30). In one embodiment, a catalytic reactor (14) includes a protective coating (58) that may be chemically removed or mechanically removed while the catalytic reactor (14) is disposed in a combustor (30).
摘要:
A mullite body comprising: a plurality of crystals, wherein about 70 percent or greater of the crystals have a crystal diameter that is within about 3 microns or less of an average diameter of the plurality of crystals, and a porosity of 55 percent or greater; and made using a process comprising: mixing precursor materials together with an average aggregate particle size of about 3 microns or smaller measured using a particle size analyzer; heating greenware in air to a first temperature such that the greenware is dried and forms calcineware, heating the calcineware in a silicon tetrafiouride atmosphere to form f lurotopaz, and heating to a second temperature so that a mullite structure is formed.
摘要:
Described is a monolithic support member comprising channels with walls separating the channels and having a coating deposited thereon, the non-coated channels having a polygonal cross-section profile, wherein the mean thickness dC of the coating in a corner of said cross-section profile is smaller than or equal to the mean thickness dE of the coating on an edge of said cross-section profile plus 85 micrometer. Also described is a method for the preparation of such coated monolithic support member. Further described is the use of such coated monolithic support member as a catalytic article in automotive exhaust gas treatment.
摘要:
There is disclosed a honeycomb structure usable as a support of a honeycomb catalyst onto which a large amount of catalyst can be loaded and which has a good purification efficiency, and the honeycomb structure includes porous partition walls 5 defining a plurality of cells to form through channels of a fluid and having a plurality of pores 10 therein, wherein a porosity of the partition walls 5 is from 45 to 70%, and in a cross section perpendicular to an extending direction of the cells, a total area of macro pores 12 having the largest pore diameter of larger than 10 µm is 50% or more with respect to a total area of the pores 10.